Rhythm versus rate control in patients with newly diagnosed atrial fibrillation: observations from the GARFIELD-AF registry

Background

Atrial fibrillation is associated with considerable morbidity and mortality. Real-world reports on the effect of early rhythm control on patient outcomes in patient with recent onset atrial fibrillation are limited.

Purpose

To assess the effect of early rhythm versus rate control on clinical outcomes in patients with newly diagnosed non-valvular atrial fibrillation.

Method

The Global Anticoagulant Registry in the FIELD-AF (GARFIELD-AF) is a non-interventional registry of adult (≥18 years) patients with newly diagnosed atrial fibrillation (≤ six weeks' duration) and at least one investigator determined risk factor for stroke. Patients were enrolled in 1317 participating sites in 35 countries between March 2010 and August 2016. Patients with permanent atrial fibrillation were excluded. Stratification to rhythm or rate control was based on treatment strategy initiated at baseline (≤48 days post enrolment). Rhythm control was defined as investigator reported initiation of rhythm control (antiarrhythmic drug(s), cardioversion, or ablation – alone or in combination with rate modifiers). Rate control was defined as investigator reported initiation of rate control and absence of rhythm control therapy. Overlap propensity weighting and Cox proportional-hazards models were used to evaluate effect on outcomes.

Results

Of 45,382 included patients, 23,858 (52.6%) received rhythm control and 21,524 (47.4%) rate control. Rates of rhythm control were similar throughout the study time period (52.7% in 2010/2011, 54.2% in 2015/2016). Patients in the rhythm control group were younger (median age (Q1; Q3) 68.0 (60.0; 76.0) versus 73.0 (65.0; 79.0)), had lower rates of prior stroke/transitory ischemic attack/systemic embolism (9.4% vs 13.0%), and a lower median GARFIELD death score (4.0 (2.3; 7.5) versus 5.1 (2.8; 9.2)). Median CHA2DS2-VASc Scores were 3.0 (2.0; 4.0) in both groups. Rate of anticoagulation treatment was similar in the rhythm and rate control group (66.0% versus 65.5%). After propensity score overlap weighting, patients of the two groups were well balanced on all observed characteristics.

Event rates per 100 person-years (95% confidence interval [CI]) over two years follow-up in the rhythm and rate control group were 2.94 (2.78–3.10) versus 4.43 (4.22–4.64) for mortality, 0.84 (0.75–0.92) versus 1.16 (1.05–1.27) for non-haemorrhagic stroke/systemic embolism and 0.84 (0.76–0.93) versus 1.16 (1.06–1.27) for major bleeding. Adjusted hazard ratios (95% CI) for the same time period were 0.85 (0.79–0.92), 0.84 (0.72–0.97) and 0.9 (0.78–1.04).

Conclusion

In this large, internation registry, a rhythm control strategy was initiated at baseline in about half of the patients with newly diagnosed non-valvular atrial fibrillation. After adjustment for confounding factors, a significantly lower risk of all-cause mortality and non-haemorrhagic stroke/systemic embolism were observed for patients that received an early rhythm control strategy.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): This work was supported by the Thrombosis Research Institute (London, UK).

Body adiposity estimated with CUN-BAE predicts atrial fibrillation: the SUN cohort

Background

Obesity is widely recognised as a strong risk factor for atrial fibrillation and recent interest has focused on epicardial fat. Although body mass index is commonly used in the clinical practice, it doesn't precisely estimate adiposity. The Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE) is an equation developed for body fat calculation, that has been previously associated with cardiometabolic disease. Our objective was to assess the association between body fat, as captured by the CUN-BAE index, and the incidence of atrial fibrillation in a prospective cohort.

Methods

The SUN project is a dynamic, prospective cohort of Spanish university graduates. A total of 20.136 participants, free of atrial fibrillation at baseline, were followed-up for a median time of 12 years, with a retention proportion of 91%. CUN-BAE was calculated for each participant taking into account only sex, age and body mass index. Incident cases of atrial fibrillation were confirmed by a cardiologist according to a prespecified protocol. Multivariable Cox regression models were used to estimate hazard ratios (HR) of atrial fibrillation according to calculated body fat.

Results

During follow-up, we identified 128 incident cases of atrial fibrillation. There was a strong direct association between a higher CUN-BAE index at baseline and incident atrial fibrillation during follow-up. In comparison to participants with a lower body fat category (median 21.3%), those with a higher category of body fat (median 34.8%) exhibited a significant 118% higher relative risk of incident atrial fibrillation (adjusted HR=2.18; 95% CI: 1.22, 3.90). For each 2-unit increase in the CUN-BAE index, atrial fibrillation risk significantly increased by 10%. The risk of incident atrial fibrillation remained significantly associated with adiposity even after further adjustment for obesity (body mass index ≥30 kg/m2) and in repeated measures analysis of the CUN-BAE index every other year.

Conclusions

Increased body adiposity, as captured by CUN-BAE index, was strongly and independently associated with a higher risk of atrial fibrillation in a Spanish cohort. These findings support the hypothesis that adiposity is closely related with arrhythmogenic mechanisms that could lead to atrial fibrillation and may be predicted using an equation to estimate body fat.

Funding Acknowledgement

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Spanish Ministry of Health and European Regional Development Fund (FEDER)

Inflammatory mediators to predict left adverse ventricular remodelling in revascularized STEMI patients

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Institute of Carlos III the Spanish Ministry of Economy and Competitiveness

Background

Primary percutaneous coronary intervention (PPCI) in patients with ST-segment elevation myocardial infarction (STEMI) improves the survival of patients. Nevertheless, some patients develop left ventricular adverse remodeling (LVAR). The main objective of this study is to find reliable prognostic biomarkers for patients developing LVAR, focusing in the role of pro-inflammatory mediators, including cell populations and secreted molecules.

Methods

We assessed the level of pro-inflammatory cell subsets, before and after the revascularization, 1 and 6 months after the PPCI, using flow cytometry. We also performed miRNAs microarray in isolated peripheral blood mononuclear cells (PBMCs), and examined the levels of 27 cytokines in patients’ serum by multiplex ELISA.

Results

We observed that levels of pro-inflammatory monocytes were increased soon after PPCI, in patients who afterward developed LVAR. Furthermore, we detected significant increase in the concentration of secreted cytokines such as IL-1b, IL-17, IFN-g and VEGF in LVAR patients post-PPCI. Moreover, specific miRNAs levels regulating these cytokines secretion, also correlated with LVAR. Multivariate regression analysis and ROC curves indicated that these inflammatory mediators were good biomarkers to correlate with the appearance of LVAR in patients. In addition, we found that the combined analysis of these biomarkers increased the specificity and sensibility to identify patients with LVAR.

Conclusion

Our data suggest that the combined analysis of these inflammatory axes and related molecules, could reliably predict LVAR in STEMI patients.

Low rate of worsening renal function after 2 years of treatment with edoxaban in patients from the ETNA-AF-Europe study

Background

Use of vitamin K antagonists (VKAs) is associated with a crude event rate of 23% per year for worsening renal function (WRF). Although non-vitamin K antagonist oral anticoagulants (NOACs) have been associated with a lower risk of longitudinal decline in renal function compared with VKAs, available evidence on renal function decline in patients using NOACs is still limited. Furthermore, renal function is a dose reduction criterion for NOACs, which poses an important question about how physicians should treat patients whose renal function worsens over time.

Purpose

To evaluate the degree of renal function decline in AF patients treated with edoxaban after 2 years of follow-up, and to investigate clinical outcomes of patients with vs without WRF in the ETNA-AF-Europe study.

Methods

ETNA-AF-Europe is a multinational, multicentre, observational, post-authorisation safety study conducted in 825 sites in 10 European countries. Results are based on a data snapshot taken on 26th October 2020 which include data up to 2 years of follow-up. Patients were excluded from the analysis population if data to calculate estimated glomerular filtration rate [eGFR] were not available for at least one of the follow-up time-points of 1-year and 2-year. We categorised patients (n=9084) into two subgroups: 1) those with WRF (i.e. ≥25% decline in eGFR from baseline; n=918), and 2) those without WRF (n=8166). eGFR was estimated using the Cockcroft-Gault formula. Baseline characteristics and annualised event rates including 95% confidence intervals were analysed using descriptive analyses.

Results

Of the 13,417 patients in ETNA-AF-Europe who were included in the 2-year follow-up analysis, 9084 were included in this subgroup analysis, of whom 56.2% were male. Baseline eGFR were similar between patients with and without WRF when comparing across the different renal function categories (Table 1). The majority of the edoxaban-treated patients did not experience WRF (89.9%) during the 2 years of follow-up. The proportion of patients with WRF (10.1%) were older, more often frail and had higher rates of underlying comorbidities, such as diabetes, hypertension and heart failure (Table 1). Patients with WRF had higher annualised event rates of all-cause and cardiovascular death than those without (3.78% vs 1.90% and 2.06% vs 0.92%, respectively). Major bleeding and stroke rates were low, but numerically higher in patients with renal worsening compared to those without WRF (Figure 1). Intracranial haemorrhage rates remained low (0.17% vs 0.19%; Figure 1) in both subgroups.

Conclusions

This subgroup analysis provides real-world evidence for a low risk of WRF in AF patients treated with edoxaban over a 2-year period. Patients with WRF had higher mortality than those without, as well as numerically higher major bleeding and stroke rates. Importantly, intracranial haemorrhage rates remained low irrespective of WRF.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Daiichi Sankyo Europe GmbH /